Scott Stringer made it official yesterday evening: He's not running for mayor in 2013, and instead will try to become city comptroller. Stringer, the Manhattan borough president, had raised an impressive amount of money for a possible mayoral bid, and he had the legislative and policy background to be a strong candidate. But in a crowded field he was going to have trouble expanding beyond his Upper West Side base. So Stringer came to the realistic conclusion that his chances are better in the comptroller contest — both because he's got some experience in government finance and because he believes that John Liu, the incumbent, won't be in the field: Either Liu follows through on his intention to run for mayor or he's too damaged, politically, by investigations into his campaign fund-raising to run for reelection.
So which of the remaining mayoral candidates benefits? All of them, if you listen to the spin from their camps. And they're not wrong: Stringer's exit gives everyone significant opportunities. Christine Quinn now has a better chance to enlarge her Manhattan vote beyond Chelsea. Bill de Blasio, trying to run distinctly to Quinn's left, gets a good shot at Upper West Side progressives mad at Quinn for helping enable Mayor Bloomberg's third term. Bill Thompson won't have Stringer competing with him for voters north of 110th Street, and Thompson can try to woo the outerborough Jewish voters who were Stringer's other natural supporters. But those are all openings, not guarantees, and all three have a lot of work to do between now and the September primary. Though if you force me to pick who could benefit most, it's probably de Blasio: He and Stringer had the most philosophical overlap, and with Quinn and Thompson known commodities, de Blasio is now likely to get more media and voter attention as a fresh alternative.
The only sure winner here, however, is Congressman Jerry Nadler. No, he's not jumping into the 2013 mayoral field. But Nadler was a key Stringer backer, he's a hero to many Manhattan progressives, and he has close ties to important labor unions. Nadler's endorsement is now up for grabs, making him very, very popular with the contenders who are still standing.